1. Field of the Invention
The present invention relates to a photosensitive resin composition, a lithographic printing plate precursor, and a method for producing a lithographic printing plate.
2. Description of the Related Art
In the related art, various photosensitive compositions have been used as a visible image forming material and a lithographic printing plate material. In particular, the development of lasers in the lithographic printing field in recent years has been remarkable, and in particular, solid lasers and semiconductor lasers having an emission region in a near infrared region to an infrared region, with a high output and a small size, has become easily available. In the field of lithographic printing, as an exposure light source when manufacturing a printing plate directly from digital data from a computer or the like, these lasers are very useful.
A positive type lithographic printing plate precursor for infrared laser has an alkali-soluble binder resin and an IR dye which absorbs light and generates heat, as essential components. In the unexposed portion (image portion), the IR dye and the like act as a development restrainer which substantially decreases the solubility of a binder resin in a developer due to an interaction with the binder resin, and in the exposed portion (non-image portion), the interaction between the IR dye and the like and the binder resin weakens due to generated heat, and the IR dye and the like dissolve in an alkaline developer, and as a result, a lithographic printing plate is formed.
As the lithographic printing plate in the related art, the lithographic printing plates described in JP2005-91429A, JP2005-258070A, JP2003-315995A, or JP2006-225432A are known.